Castillo said the district expects to provide larger charter buses, seating up to 56 passengers, starting Wednesday to ease the crowding seen on some buses Monday. One transit official at the Escondido Transit Center said buses were “packed to the gills” during the morning rush hour. Another official at the Vista Transit Center said some buses had been delayed because of early morning traffic on Route 78.

The transit district has contracted with US Coachways to provide charter coaches for its 620 Sprinter Express bus route. The older buses, which don’t have fare boxes, are “a stopgap” measure until more modern private buses arrive tonight and go into service Wednesday, Castillo said.

Castillo said the agency’s contract with US Coachways was not immediately available.

The agency’s Sprinter maintenance contractor, Bombardier, was still searching for replacement brake parts Monday, Castillo said. No purchase order had been placed, she added.

The search for comparable parts is difficult because the Sprinter is one of only a handful of diesel, multiple unit light rail trains in the United States, transit officials said last week.

If existing parts aren’t available, a custom order from Europe would have to be made — creating a longer Sprinter shutdown, officials said.

Castillo said the transit agency would share a timeline with the public once decisions were made on how to proceed. “We’re still in the process of figuring that (timeline) out and trying to get it accelerated,” Castillo added.

She said the agency had not hired any new contractors to aid the search for parts, instead relying on Veolia Transportation, which operates the trains, and Bombardier.

Castillo also said the agency has hired additional, temporary customer service workers to help riders at local transit stations.

The Sprinter’s fifth anniversary celebration was canceled last week because of the shutdown.